Wrench having yieldably biased pivotal outer jaw



Aug. 28, 1956 H. sT. PIERRE 2,760,395

WRENCH HAVING YIELDABLY BIASED PIVTAL OUTER JAW Filed March 25, 1954 HENRY ST PIERRE ATTORNEY United States Patent C) WRENCH HAVING YIEL'BABLY BIASED PIVT-AL OUTER .JAW

Henry St. Pierre, Worcester, Mass.

Application March 25, 1954,Sera'l"1510.418525` 2 Claims. (.Cl. 81-101) This invention relates to a new ,and improved wrench, being particularly adaptable to Stillson or pipe wrenches although the inventive 'features 'may be -nt-ilized in other wrenches of .the ,type having relatively `rectilinearly movable jaws.

The principal 4object ofthe invention resides 'in the provision of a lnew and improved wrench'having a relatively xed ljaw and a movable pivotally lmounted jaw \wherein new and improved spring means -is provided forma'intaining the movable jaw in an intermediate 'inactive position, said spring means vbeing located a-t each side of the -shank of the movable jaw i-n a projection on the fixed jaw or the handle therefor, said spring means being located in o'set -relation with respect -to-each other =for thepurpose of providing Sfor a slightly tilted intermediate inactive position of the movable jaw such that .it :can .be moved `away from .the lixed Ajaw to .a greater .extent `tha-n possible motion toward the iixed jaw ior the purpose of :increasing the grip of the jaws on a member held between them.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings, in which:

Fig. 1 is a view in elevation of a wrench according to the invention;

Fig. 2 is an enlarged section on line 2 2 of Fig. 1;

Fig. 3 is an edge view of the jaw shown in Fig. 2, looking in the direction of arrow 3;

Fig. 4 is an enlarged section on line 4 4 of Fig. 1;

Fig. 5 is an edge view thereof, looking in the direction of arrow 5 in Fig. 4;

Fig. 6 is an enlarged section on line 6 6 of Fig. 1;

Fig. 7 is a section on line 7 7 of Fig. 6;

Fig. 8 is an edge view of the spiral handle, looking in the direction of arrow 8 in Fig. 1;*

Fig. 9 is a section on line 9 9 of Fig. 8; and

Fig. 10 is a section through the nut shown in Fig. 1 and the shank in mesh therewith.

The present invention has been illustrated as applied to a pipe or Stillson wrench but the invention may also be applied to other types of wrenches and particularly those which include a handle with la fixed jaw, and a shank movable in parallel relation to the handle and having a jaw for movement to and from the fixed jaw. In the present case, the wrench is provided with an elongated tapered handle 10 provided with elongated tapered grooves 12 which provide for suicient strength in the handle with a lesser amount of material. At its smal-ler free end, the handle 10 is formed on a spiral as is clearly shown at 14, this spiral formation providing for a greatly improved grip on the part of the operator. The cross sectional shape of the handle is generally oval as seen in Fig. 9 and the spiral formation is interrupted by the longitudinally extending grooves 12 as clearly shown in Fig. 1.

The handle 10 is provided in this case .with an integral projection 16. This projection may of course take the form of a sepa-rate attached frame if desired, as well Ace known 4in the In any event, vthe projection '1.6 ,is apertured as usual, and receives in loose sliding engagement a movable shank 18 having a jaw 20. This shank is provided with threads 22 at either side thereof vfor en gagement with interna-l threads of a relatively large nut 24. The nut 24 is held against axial :movement between the projection I6 and a spur 2,6, and .upon rotation of nut 24, the lshank 18 will .be 4rectilinearly translated so .as to bring the jaw l22 `toward .and `from a jaw 28 which lis mounted in fixed relation .to .the handle 10 as shown.

' The nut 24 is thickly plated with a soft lmetal generally indicated at 30. This may be brass or similar material and it kprovides `for .easier .and Aquicker rotation of .the nut on ,the `shank, .so that the adjustment of Vthe jaws may be made more quickly.

Referring now .to lFigs. 2 and 3, Vit will .be seen -t-hat the jaw 20 is provided atits gripping surface -with a series ,of gripping .teeth 32 cutfon the :arcs ofcircles, the centers of which ,are located .to .the right in Fig. 2. Each of the teeth .32 .therefore forms an arch which is concave in a direction fac-ingthe shank 18.

Referring to Figs. -4 and 5, it is seen that lthe iiXed jaw 28 is provided with similar teeth 34 formed on the arcs of circles, .the icenters of which are to the left in Fig. 4, so that the individual teeth present concave gripping edges .extending in .the direction shown, i. e., oppo- .sitely to the .teeth of Fig. 2.

When these :two jaws grip `between them some object and the handle of the wrench is moved Vin -a clockwise direction in Fig. l, which is the normal motion for tightening .one .object .relative to another, it will .he seen that 4all lof .the teeth 32 .and x34 -present their :concave edges to the object gripped and therefore act in the manner of arches or the like so that each tooth is stronger than a straight tooth both because it is longer and because it presents an arched shape. Furthermore, the object gripped will be gripped by a plurality of teeth at dilerent points along their edges, whereas in the case of straight teeth, one tooth alone or perhaps two teeth would grip an object along the length of each such tooth. It will therefore be seen that the present spiral or arcshaped teeth are much stronger and grip better than teeth of the prior art.

The aperture in the projection 16 is indicated at 36 and it is made sufliciently large so that the shank 18 is only loosely contained therein as is clearly indicated in Fig. 7. The less the teeth 22 are interfered with during rectilinear movement of shank 18, the smoother and easier the nut 24 will operate. The shank is held in a pivotal relation in the aperture '36 and in the present case, spring devices are provided, one at each side of the shank, so as to yieldably resist rotational motion of the shank in either a clockwise or counterclockwise directioninFig. 1.

Each spring device comprises a shoe or the like 38 which is provided with a transverse section that is made concave (see Figs. 4 and 6) in order to conform to the shape of the teeth on the shank 18. The shoes are also concave in the direction of their lengths. In this way there is little or no resistance to the motion of the shank due to the shoes 38. The longitudinal edges of these shoes may be turned out slightly as at 4t) in order to provide smooth non-interfering edges, and the ends of the shoes are bent reversely (see Fig. 7) at 42.

The bent-away ends form feet at the ends of the shoes for engagement with undercut shoulders 44 which hold the shoes loosely in openings 46, there being one such opening and one such shoe at each side of the shank as clearly shown. The shoes 38 are yieldingly pressed toward the aperture 36 by means of coil springs 48, and it will be seen that this construction provides for holding the shank yieldably in an intermediate non-operating central position without interfering with the rectilinear motion of tthe shank under inuence of the nut, so that a very smooth action is obtained while still providing an improved holding means for the shank, allowing for pivotal motion thereof in either direction in Fig. l.

It is preferred that the spring device at the side of the shank 18 away from the jaws shall be advanced or oifset forwardly with relation to the other spring device, so that the shank is actually yieldingly held in a slightly canted relation in a counter-clockwise direction. The result of this construction is that the jaw 20 and shank 18 may be pressed away from jaw 28, Without of course rotating nut 24, to a greater degree than any possible motion in the opposite direction, and this is advantageous in grasping or gripping Van object between the jaws.

It will be seen that this invention provides for an extremely smoothly adjusted wrench which acts to grip with greater force and is easier to apply to an object to be gripped.- The jaws themselves present better gripping surfaces, the movable jaw is moved easier and smoother, and the handle of the wrench provides for a better gripping by the user and at the same time presents a wrench of relatively light weight as compared with the strength and gripping action thereof.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. A Wrench comprising a frame having a xed jaw, an apertured projection associated with the frame, a pair of recesses Within the projection and intersecting the aperture at opposite sides thereof, a movable jaw, a shank therefor, said shank being located in the aperture, a spring device in each recess bearing on the shank at opposite sides thereof and yieldably holding the same in an intermediate inactive pivotal position relative to the frame, each spring device comprising a shoe having a concaved shape with the ends thereof bent out and received in its recess in the projection, undercut shoulders in each recess receiving and holding the bent out ends, and a spring urging the sh-oe outwardly of its recess to engage the shank.

2. A wrench comprising a frame having a Xed jaw, an apertured projection associated with the frame, a pair of recesses within the projection and intersecting the aperture at opposite sides thereof, a movable jaw, a shank thereon, said shank being located in the aperture, a spring device in each recess bearing on the shank at opposite sides thereof and yieldably holding the rsame in an intermediate inactive pivotal position relative to the frame, each spring device comprising a shoe having a concave section to fit the shank smoothly, means loosely holding each shoe in its recess, and a spring urging each shoe into contact with the shank.

References Cited in the ile of this patent UNITED STATES PATENTS 507,407 Bole Oct. 24, 1893 588,751 Lownes Aug. 24, 1897 850,254 Robbins Apr. 16, 1907 922,866 Edwins May 25, 1909 1,027,782 Watrous May 28, 1912 1,125,946 Bovee Ian. 26, 1915 1,357,848 Goes Nov. 2, 1920 1,522,804 Carlson Ian. 13, 1925 1,565,338 Thewes Dec. 15, 1925 1,661,448 Taylor Mar. 6, 1928 1,753,773 Champion Apr. 8,1930

2,181,835 Place Nov. 28, 1939 2,312,090 Gorrell Feb. 23, 1943 2,680,396 Wrightv .Tune 8, 1954 

